The North American Numbering Plan (NANP) was established in the early 1940's, when American Telephone and Telegraph (AT&T) realized that the expansion of long distance calling should be consistent with the ultimate incorporation of all public switched telephone networks into an integrated nation-wide network. Under the NANP, the United States and Canada were divided into eighty-three “zones,” called Numbering Plan Areas (NPAs), where each area is identified by three digits referred to as “Numbering Plan Area codes” or “area codes.”
Within each zone or area code, a central office is represented by another three-digit code called the central office code (NXX). The central office code is used for routing calls and for rating and billing calls. Finally, a 4-digit number identifies the particular telephone line on the central office switch. Thus, in the United States, a telephone number is composed of a 3-digit numbering plan area code (NPA), a 3-digit central office code (NXX), and a 4-digit line number (XXXX).
The rapid growth of new telecommunication services over the past several years, exacerbated by the former practice of distributing numbers to service providers in blocks of 10,000 numbers, resulted in the rapid depletion of available telephone numbers. To appreciate the rapid growth of use of telephone numbers, consider that in the ten-year period between 1984 and 1994, only nine new area codes were activated while in 1997 alone, 32 new area codes were activated.
Even in the area codes that are experiencing depletion, however, it is estimated that a relatively low percentage of individual telephone numbers are actually assigned to customers. Furthermore, typically the same service provider will have pockets within the service provider's service area where there are more customers than available numbers and other pockets where there are more telephone numbers than are needed. Hence, a need existed to make more efficient use of numbering resources.
To address this problem, the Federal Communications Commission (FCC), in order number FCC 99-122 issued under the Telecommunications Act of 1996, mandated Number Pooling, a system for reporting and allocating numbers in blocks of 1,000 telephone numbers instead of blocks of 10,000 telephone numbers. The FCC requires the donation of all blocks held by service providers if the blocks have a “contamination” level of less than 10%. A contaminated number is a number that is not available for assignment (e.g., the number is already in use). Blocks are donated to the pool for the rate area from which the numbering resources are assigned. All Local Number Portability (LNP)-capable service providers must participate. Number portability refers to the ability of users of telecommunications services to retain, at the same location, existing telecommunications numbers without impairment of quality, reliability, or convenience when switching from one telecommunications carrier to another.
An Industry Inventory Pool is maintained in thousands-block (i.e., a block of a thousand numbers) number pooling. The pool contains groups of unassigned blocks of a thousand numbers in a given rate area and is administered by a Pooling Administration (PA) for purposes of assignment to certified carriers participating in thousands-block number pooling.
The Pooling Administration is an independent third-party entity. The FCC mandates the accounting for and reporting of all numbering resources in six primary categories. Service providers must maintain records on number usage and report semi-annually to the Pooling Administration. The Pooling Administrator tracks numbering resources and manages the donation and assignment of numbering blocks within the pool based on the information obtained within the records.
At the time a service provider donates a block of numbers to the pool, the service provider must inform the Number Portability Administration Center (NPAC) of the contaminated telephone numbers contained within the donated block. Contaminated telephone numbers, as stated above, are those telephone numbers that are not available for assignment, for example: numbers that are already in use. Upon receiving a block of numbers from a service provider, NPAC broadcasts a message to all providers, listing the contaminated (active) numbers.
A service provider can also request a block of numbers from the Pooling Administration, based on the needs of the service provider. The Pooling Administrator coordinates the allocation of numbers to a particular service provider with the Number Portability Administration Center (NPAC) service management systems (SMSs). The NPAC SMSs are regional databases that contain all necessary routing information on ported telephone numbers and facilitate the updating of the routing databases of all subtending service providers in the portability area.
If the Pooling Administration approves the request, the Pooling Administration requests NPAC to release a block of numbers to the requesting service provider. When NPAC releases the block to the service provider, NPAC broadcasts a message to all the service providers so that the service providers can update their switches so that calls can be routed correctly. Contained within the message is: the area code, central office code and the leading digit of the released thousand-block, the local routing number (LRN) of the donating service provider's switch, global title translation (GTT) which identifies the features available on the switch, and an identifier for the receiving service provider. The message broadcast by NPAC is not directed to components of the service provider such as the billing system and facilities systems mentioned above. Furthermore, the message broadcast by NPAC does not contain a list of contaminated numbers in the block and likewise does not contain the LRN of the receiving service provider's switch, but instead contains the LRN of the donating service provider's switch. As a result, components (such as facilities management and billing components) of the receiving service provider and other service providers may not know the LRN of the switch to which the uncontaminated numbers will be attached, and will not know what numbers in the block are already in use.
Hence a need exists to overcome the drawbacks of the prior art. In particular, a need exists for a system and method for providing components of a service provider with a list of contaminated numbers and for informing components of a service provider with the LRN of the switch to which the uncontaminated numbers will be attached.